Energy extraction performance for a diode-pumped CPA system in Yb-doped materials at low temperature

The observed absorption and emission spectra ofYb:YLF at low temperature show that energy extraction efficiency is improved drastically with the reduced saturation fluence of 9 J/cm2 and the expanded spectral width of 38 nm. Yb:glass also shows a similar temperature dependence of the spectral characteristics to that of Yb:YLF.